378 THE SALMON RIVERS OF SCOTLAND 



Before leaving this source of the Boon, it is proper to notice that 

 here already exist the conditions under which the regulation of 

 waterflow can be carried out, so as to store water in winter, increase 

 the natural flow in summer, and, if need be, send a moderate flood 

 down the river, when the fishing would be benefited thereby. 

 Eeference may be made to the chapter dealing with the Helmsdale 

 for a discussion of the benefits to be derived from well-regulated 

 operations of this kind. 



About 2J miles below Loch Doon the river, when opposite 

 Dalmellington, widens out into a shallow but extensive diverticulum, 

 known as Bogton Loch. There is something almost hideous in the 

 name, but it is expressive. It is a weedy boggy place, and the 

 stronghold of pike. Below this the river commences to wind 

 about, and this it continues to do to an ever-increasing extent till it 

 reaches the sea, although it does not cross the 500 feet contour till 

 Patna is reached. A couple of miles below Bogton a small burn 

 enters on the right, called the Eough Burn, which passes through 

 most extensive ironworks, and receives pollutions of various kinds. 

 In crossing the flat grassy meadow between the works and the 

 river, the impurities are subjected to a certain amount of land 

 treatment, but a sufficient amount of the discharge is direct enough 

 to have a high temperature on entering the river. An examination 

 trap exists here, and on one occasion, having the curiosity to test 

 the temperature, I found it 96 F. Loch Doon on the same day 

 was 55, so the contrast was violent for a creature like the salmon 

 or trout, whose blood is only slightly higher than the temperature 

 of the water in which it swims. Before now, dreadful and sudden 

 mortality has occurred amongst the fish in the Doon. I don't know 

 if it was these particular ironworks which were to blame, but it was 

 owing to this class of pollution that, on five separate occasions 

 between 1870 and 1893, serious destruction of fish occurred. How- 

 ever, I don't think this is likely to happen again. 



Other pollution troubles have, in the past, arisen from a large 

 blanket work called the Skeldon Mills, several miles lower down. 

 The scour-wash was run into a pond, where the soapy waste became 

 very foul ; but the sluice of this pond was some time ago placed 

 under the control of the river-watcher, who was able to run it off 

 at times when it was likely to do a minimum of harm to the river. 

 The mills have since, I understand, been closed. The dam dyke in 

 connection with these mills, as well as two other dykes within a 

 few miles, are fortunately not serious obstructions. 



